The purpose of the project is to investigate the biological roles of members of the chemokine family of cytokines by studying chemokine actions in vivo, particularly in mouse models of infectious disease, inflammation, and angiogenesis. These experiments will provide important information for understanding in which therapeutic contexts in humans manipulating the chemokine system might be beneficial. This laboratory discovered two mouse chemokines, Crg-2 and Mig. Crg-2 is the mouse homologue of the human chemokine IP-10, and the murine Mig (MuMig) was used to identify a human homologue, HuMig. Crg-2/IP-10 and Mig are related interferon-gamma inducible chemokines that preferentially target lymphocytes, acting as chemotactic factors for activated T cells and natural killer cells. It is our hypothesis that these chemokines are important for recruiting T cells to sites of inflammation and immune response. In addition to studying Mig and Crg-2/IP-10, for a number of in vivo models the project will include a systematic evaluation of the expression of multiple chemokines in order to develop a more comprehensive understanding of the roles for chemokines in these reactions and to identify which are likely to be of principle importance within a particular context. The project has involved analyzing chemokine expression in the infections of mice with the protozoan pathogens Toxoplasma gondii and Plasmodium yoellii, the trematode pathogen Schistosoma mansoni, vaccinia virus, and the opportunistic bacterial pathogen Mycobacterium avium. Mice have been derived with targeted disruption of the mig gene and neutralizing antibodies have been raised against Mig as well as Crg-2/IP-10. In addition to most of the experimental infections listed above, the mice lacking Mig have been analyzed after infections with listeria, salmonella, and francisella bacteria, ectromelia virus, and the fungal pathogen cryptococcus. These mice are also being evaluated for their inflammatory responses in delayed- type hypersensitivity and in contact hypersensitivity. In related experiments, recombinant vaccinia virus have been made expressing Mig and Crg-2/IP-10, and the effects of viral production of these chemokines is being analyzed during infections of mice having a variety of defined immunodeficiencies. Finally, the project involves experiments on the ability of Mig and Crg-2/IP-10 to inhibit angiogenesis, particularly in tumor growth. Evaluation of models of infection and inflammation includes monitoring mortality and other clinical parameters, titering of organisms recovered from infected mice, analysis of immune/inflammatory responses in tissues by quantifying expression of chemokine and chemokine mRNAs and by histology, in situ hybridization, immunohistochemistry, and flow cytometry, and analysis of other aspects of immune response by determining antibody production and production of cytokines after in vitro restimulation of cells isolated from infected animals. Evaluation in models of angiogenesis involves quatification of new blood vessel and tumor growth.